When I Enter the last level of Ceylon I can't finish it. I do everything as it says in the strategy guide,(I Imprison the white alligator, lower all of the swings), then finally, I get to the artifact there, and I fall in to the water, so I try, cutting through vines underwater, and it's as if there were an invisible wall, that won't let me go further into the vines/cut them. And this happened 3 times to me.